Map of Tungkillo, SA 5236

Tungkillo (34°49′S 139°04′E, postcode 5236, altitude 299m) is a town in South Australia, located approximately 5 km (3.1 mi) south of Mount Pleasant. It sits on Adelaide-Mannum Road, 60 km (37 mi) north-east of the state capital, Adelaide and 25 km (16 mi) north-west of Mannum. At the 2006 census, Tungkillo had a population of 360.

Tungkillo was originally the name of a mine located south of Palmer, which opened in 1847. In 1848, a town was surveyed at the mine, The present-day town was settled by Samuel Patten in 1861, who called it South Petherton (after the Somerset town of South Petherton from which his family originated). The name of South Petherton was officially altered on 24 January 1906 to Tungkillo, although the two names were used interchangeably as late as 1936.